Superconductivity beyond the Pauli limit in high-pressure CeSb2

Oliver P. Squire; Stephen A. Hodgson; Jiasheng Chen; Vitaly Fedoseev; Christian K. de Podesta; Theodore I. Weinberger; Patricia L. Alireza; F. Malte Grosche

arXiv · 2211.00975

Superconductivity beyond the Pauli limit in high-pressure CeSb2

Oliver P. Squire·Stephen A. Hodgson·Jiasheng Chen·Vitaly Fedoseev·Christian K. de Podesta·Theodore I. Weinberger·Patricia L. Alireza·F. Malte Grosche

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Abstract

We report the discovery of superconductivity at a pressure-induced magnetic quantum critical point in the Kondo-lattice system CeSb2, sustained up to magnetic fields that exceed the conventional Pauli limit eight-fold. Like CeRh2As2, CeSb2 is locally non-centrosymmetric around the Ce-site, but the evolution of critical fields and normal state properties as CeSb2 is tuned through the quantum critical point motivates a fundamentally different explanation for its resilience to applied field.

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Oliver P. Squire, Stephen A. Hodgson, Jiasheng Chen, Vitaly Fedoseev, Christian K. de Podesta, Theodore I. Weinberger, Patricia L. Alireza, F. Malte Grosche. 2022-11-02. Superconductivity beyond the Pauli limit in high-pressure CeSb2. https://arxiv.org/abs/2211.00975

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